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Synthesis of Planar-Chiral[2.2]Paracyclophane-Based Oxazole-Pyrimidine Ligands and Application in Nickel-Catalyzed 1,2-Reduction ofα,β-Unsaturated Ketones

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Chinese Journal of Chemistry 2024年第7期42卷 705-710页

作者： Juan Wang Qing-Xian Xie Xiang Li Chang-Bin Yu Yong-Gui Zhou School of Chemistry Dalian University of Technology2 Linggong RoadDalianLiaoning 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China

The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric *** them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural ***,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%***,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.

关键词： Oxazole-pyrimidine ligands Planar chirality Nickel Hydroboration Asymmetric synthesis

Carbon nanocages bridged with graphene enable fast kinetics for dual-carbon lithium-ion capacitors

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Green Energy & Environment 2024年第3期9卷 573-583页

作者： Shani Li Yanan Xu Wenhao Liu Xudong Zhang Yibo Ma Qifan Peng Xiong Zhang Xianzhong Sun Kai Wang Yanwei Ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Innovation Academy for Green Manufacture Beijing100190China Beijing Institute of Technology Beijing100081China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China

Lithium-ion capacitors(LICs) combining the advantages of lithium-ion batteries and supercapacitors are considered a promising nextgeneration energy storage device. However, the sluggish kinetics of battery-type anode cannot match the capacitor-type cathode, restricting the development of LICs. Herein, hierarchical carbon framework(HCF) anode material composed of 0D carbon nanocage bridged with 2D graphene network are developed via a template-confined synthesis process. The HCF with nanocage structure reduces the Li^(+) transport path and benefits the rapid Li^(+) migration, while 2D graphene network can promote the electron interconnecting of carbon nanocages. In addition, the doped N atoms in HCF facilitate to the adsorption of ions and enhance the pseudo contribution, thus accelerate the kinetics of the anode. The HCF anode delivers high specific capacity, remarkable rate capability. The LIC pouch-cell based on HCF anode and active HCF(a-HCF) cathode can provide a high energy density of 162 Wh kg^(-1) and a superior power density of 15.8 kW kg^(-1), as well as a long cycling life exceeding 15,000cycles. This study demonstrates that the well-defined design of hierarchical carbon framework by incorporating 0D carbon nanocages and 2D graphene network is an effective strategy to promote LIC anode kinetics and hence boost the LIC electrochemical performance.

关键词： Hierarchical carbon framework Nanocage ZIF Graphene Lithium-ion capacitors

Revealing the Void Formation Mechanism during Superplastic Deformation of a Fine-Grained Ni-Co-Base Superalloy

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 915-920页

作者： Rashad AAl-Hammadi Rui Zhang Chuanyong Cui Zijian Zhou Yizhou Zhou Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The mechanism behind void formation during superplasticity remains a subject of *** study presented a novel insight into the void formation in a fine-grained Ni-Co-based superalloy during *** was observed that the dissolution ofγ′-particles resulted in the creation of vacancies due to differences in atomic size between the matrix and the *** vacancies acted as inclusions,leading to the formation of ***,excessive void formation correlated with higher particle dissolution was experimentally observed,highlighting a direct relationship between void formation and particle dissolution.

关键词： Superplasticity Void formation Ni-Co-based superalloy Microstructure

From the perspective of experimental practice: High-throughput computational screening in photocatalysis

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Green Energy & Environment 2024年第1期9卷 1-6页

作者： Yunxuan Zhao Junyu Gao Xuanang Bian Han Tang Tierui Zhang Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Institute for AI Industry Research(AIR) Tsinghua UniversityBeijing100084China

Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is now generating widespread interest in boosting the conversion efﬁ-ciency of solar *** the past decade,computational technologies and theoretical simulations have led to a major leap in the development of high-throughput computational screening strategies for novel high-efﬁciency *** this viewpoint,we started with introducing the challenges of photocatalysis from the view of experimental practice,especially the inefﬁciency of the traditional“trial and error”***-sequently,a cross-sectional comparison between experimental and high-throughput computational screening for photocatalysis is presented and discussed in *** the basis of the current experimental progress in photocatalysis,we also exempliﬁed the various challenges associated with high-throughput computational screening ***,we offered a preferred high-throughput computational screening procedure for pho-tocatalysts from an experimental practice perspective(model construction and screening,standardized experiments,assessment and revision),with the aim of a better correlation of high-throughput simulations and experimental practices,motivating to search for better descriptors.

关键词： Photocatalysis High-throughput computational screening Photocatalyst Theoretical simulations Experiments

Advances of graphdiyne-supported metal catalysts in thermocatalytic reactions

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Nano Research 2024年第4期17卷 2223-2233页

作者： Jia Yu Yida Yang Yuliang Li Changyan Cao Weiguo Song Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

supported metal catalysts are widely used in the modern chemical *** electronic interaction between supports and active components is of great significance for heterogeneous ***(GDY),a new type of carbon allotrope with sp-hybridized carbon atoms,πconjugate structure,and electron transmission capability,is a promising candidate as catalyst *** years have witnessed the rapid progress of GDY-supported metal catalysts for different catalysis *** that most processes in the current chemical industry are thermocatalytic reactions,we herein give an overview about the advances and particular characteristics of GDY-supported catalysts in these *** geometric structure and electronic properties of GDY are first ***,the synthesis methods for GDY-supported metal catalysts and their applications in thermocatalytic reactions are discussed,in which the effect of electronic interaction on catalytic performance is ***,the current challenges and future directions of GDY-supported metal catalysts for thermocatalysis are *** is expected that this review will enrich our understanding of the advances of GDY as a superior support for metal catalysts in thermocatalytic reactions.

关键词： graphdiyne metal catalysts thermocatalytic reactions heterogeneous catalysis

Evolution of hollow nanosphere to microtube in the self-assembly of chiral dansyl derivatives and inversed circularly polarized luminescence

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Chinese Chemical Letters 2024年第7期35卷 285-290页

作者： Sifan Du Yuan Wang Fulin Wang Tianyu Wang Li Zhang Minghua Liu Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China National Laboratory for Molecular Science(BNLMS) CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Here,we designed asymmetric(m DS)and symmetrical(d DS)chiral V-shaped molecules by linking one or two dansyl groups to trans-1,2-cyclohexane diamine and investigated the solvent-regulated structural transformation and inversed circularly polarized luminescence(CPL)in the *** increasing water volume fraction(fw)in the mixed solvent of water/acetonitrile,asymmetric mDS selfassembled into hollow nanospheres and microtubes,while solid nanospheres and solid microplates were corresponding to symmetric d *** this transformation process,the emission of m DS and d DS was changed from yellow-green to blue and cyan color,which was ascribed to twisted intramolecular charge transfer(TICT)and locally excited(LE)fluorescence of V-shaped DS *** conformation of N,Ndimethyl groups with respect to naphthalene ring also led to the transformation of *** tubular and platelike structures had stronger and reversed CPL signals in comparison with spheroidal *** chiral information of DS assembly could be effective transferred to achiral Nile red via co-assembly strategy,which endowed Nile red exhibiting inversed induced CPL signal regulated by water *** work provides a method for achieving a variety of self-assembled structures with adjustable chiroptical properties.

关键词： CPL inversion Hollow structure Self-assembly Dansyl Chirality transfer

Two-Dimensional Perovskite Single Crystals for High-Performance X-ray Imaging and Exploring MeV X-ray Detection

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Energy & Environmental Materials 2024年第1期7卷 139-146页

作者： Xieming Xu Yiheng Wu Yi Zhang Xiaohui Li Fang Wang Xiaoming Jiang Shaofan Wu Shuaihua Wang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Division of Nuclear Technology and Applications Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection ***,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,but they are mostly used in low-energy(≤130 keV)*** detection of MeV X-rays,which ensure thorough penetration of the thick shell walls of containers,trucks,and aircraft,is also highly desired in practical industrial ***,scintillation semiconductors for high-energy X-ray detection are currently ***,This paper reports a 2D(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single crystal with outstanding sensitivity and stability toward X-ray radiation that provides an ultra-wide detectable X-ray range of between 8.20 nGy_(air)s^(-1)(50 keV)and 15.24 mGy_(air)s^(-1)(9 MeV).The(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single-crystal detector with a vertical structure is used for high-performance X-ray imaging,delivering a good spatial resolution of 4.3 Ip mm^(-1)in a plane-scan imaging *** ionic migration in the 2D perovskite enables the vertical device to be operated with hundreds of keV to MeV X-ray radiation at high bias voltages,leading to a sensitivity of 46.90μC Gy_(air)-1 cm^(-2)(-1.16 Vμm^(-1))with 9 MeV X-ray radiation,demonstrating that 2D perovskites have enormous potential for high-energy industrial applications.

关键词： MeV X-ray detection single-crystal X-ray detectors two-dimensional perovskites X-ray imaging

Revealing the Regulation Effect of Surface Charge at Aromatic Interface to Dynamic Conformational Changes of α-Synuclein at Early Aggregation Stage

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Chinese Journal of Chemistry 2024年第16期42卷 1867-1876页

作者： Yuqi Zhang Lie Wu Xiue Jiang State Key Laboratoryof Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun Jilin 130022China Schoolof Applied Chemistry and Engineering University of Science and Technology of ChinaHefei Anhui 230026China Research Center for Analytical Science College of ChemistryNankai UniversityTianjin 300071China

The aggregation ofα-synuclein(α-syn)is strongly influenced by membrane interfaces,but the mechanism of transition from monomers to oligomers at early aggregation stage is not ***,we investigate the adsorption and structure changes ofα-syn on oppositely charged aromatic interfaces through in-situ surface-enhanced infrared absorption(SEIRA)spectroscopy and nano-IR *** results show that the synergy of electrostatic and hydrophobic interactions leads to a“fast-slow”two-step aggregation pathway on negatively charged *** adsorption induces the formation of an extended helix structure and subsequently partial helix unwinding in NAC region,which enables the hydrophobic stacking between nearby NAC *** antiparallel β-sheet rich aggregates are gradually emerging as further interactions of monomers with the fast formed“first layer”.Monomers electrostatically adsorb on positively charged interface by C-terminus with NAC region and N-terminus stretched in solvent,which serve as an aggregation core and induce further adsorption and gradual formation of aggregates with C-terminus *** results demonstrate the modulation of surface charge and synergy of electrostatic and hydrophobic interactions on the interaction modes and aggregation pathways,which provide insights into dynamic conformation changes ofα-syn at early aggregation stage and imply the important role of spatial-temporal heterogeneity of membranes inα-synucleinopathies.

关键词： α-Synuclein Interface Early aggregation IR spectroscopy Surface analysis Analytical methods Proteins Dynamic monitoring

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by Electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： Yong-Chao Gai Rui Zhang Chuan-Yong Cui Zi-Jian Zhou Yi Tan Yi-Zhou Zhou Xiao-Feng Sun Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation Electron beam smelting Tensile strength